def roman(n: int) -> str:
    result: str = ''
    dict_rim: dict = {1000:'M', 900: 'CM', 500:'D', 400: 'CD', 100: 'C', 90: 'XC', 50:'L', 40:'XL', 10:'X', 9:'IX', 5:'V', 4:'IV', 1:'I'}
    for arabic in dict_rim:
        result += n // arabic * dict_rim[arabic]
        n %= arabic
    print(result)
    return result

assert roman(10) == 'X'
assert roman(18) == 'XVIII'

